Transcript Audio Hi-Fidelity Amplifier

A New Pedagogy in Electrical
and Computer Engineering:
A Conceptual Approach
Zeynep Dilli1, Neil Goldsman,
Janet A. Schmidt, Lee Harper and
Steven I. Marcus
University of Maryland, College Park
Dept. of Electrical and Computer Engineering
(1) [email protected]
Research Problem
Can we teach elements of advanced
technology at an early level on a
conceptual basis?
Hypothesis:
We can teach college-level electronics
with applications to high-school
students by emphasizing concepts.
Introduction
• Developed an experimental
program for high-school students
• Covers fundamental ECE areas
• Lecture and laboratory components
• Uses concepts and experience
rather than higher mathematics
and theory
• Enthusiastic student response:
Successful lab experiments, good
exam results, survey answers
Program Goals
• Teach college-level electronics with the following
features in mind:
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–
–
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Enjoyable experiential introduction to ECE
Teach within context of a specific project or application
Hands-on laboratory experience
Conceptual background for later analytical study
• Providing
– Early exposure to ECE material
– Relevance and contribution of ECE to daily life
– Assistance for an informed career choice
• Evaluate the conceptual vs. mathematical
approach
Syllabus Design
• Distillation of sophomore & junior level college
courses
• Topics introduced:
– Overview of ECE
– Basic electronics & signal concepts
– PN-junction diodes, operational amplifiers, filtering,
bipolar junction transistors
– Basic hi-fi amplifier design, implementation and
fabrication
– Digital logic & digital circuits, computer technology
– Opto-electronics
• Kolb Learning Styles represented: Convergers
and Assimilators
Syllabus Features--Practical Links
• Immediate links to the real world for every
syllabus point
– Electric field concept  cathode ray tubes
– Frequency/amplitude of signals  pitch and loudness
of musical notes
– Rectification  AC-DC conversion, power supplies
– Operational amplifiers  summing, subtracting,
differentiating amplifiers
– Filtering  Stereo equalizers
– Hi-fi audio amplifier: Students fabricated their own
– Digital logic design  Vending machine algorithm
– Photonics  Arcade game LaserAim
• Getting students to identify the fruits of
technology in daily life; contributing to selfmotivation
Practical Link Example:
Hi-fi Amp Project
Two-channel amp schematic
Optional tone control circuit
Hi-fi Amp Project
Students built their own
amplifiers, taking home
working electronics of
their own handiwork and
experience…
…a piece of electronics
that concretely
illustrates the first ¾ of
the course using sound
(and vision, and solder
scent), as well as
intellect.
Hi-fi Amp Project
Syllabus Features--Experiment Rewards
• Every subject had accompanying
experiments
• Designed for immediate sensory
feedback
– LEDs as current or level indicators
– LEDs as 1/0 indicators
– Computer interface keeping score for the
arcade game
• Physical reinforcement to the more
abstract concepts
Experiment Design
Example
Summing amplifier experiment
BJT basics experiment;
bottom: circuit, right: lab sheet
Sensory Feedback Example
Hit indicators
Target indicators
LaserAim game
Shows connection: photonics, electronics,
computers & optical communications
Targets
Implementation
• Morning lecture, afternoon lab, five
days a week
• Standard lab setup, working in pairs
except for individual hi-fi amp fab
• Empty lab templates provided to
indicate what should be observed
• Co-curricular modules: Biotechnology
and artificial intelligence discussions;
laser sensor lab tour
Program Outcomes
• Focus groups, exam, student comments, survey
• Exam results: six students got 90% or higher
• Example questions:
(Sophomore level)
(Junior level)
Program Outcomes
• Focus groups & end-of-semester
surveys identify benefits for students
and educators
• Student gains:
– Ability of identifying ECE in daily life
– Hands-on experience: lab equipment and
procedure, debugging experience
– “It works!”
– High-average in mid-program exam;
working, practical, packaged audio
amplifiers
– Informed career decision
Program Outcomes
• Educator gains:
– Early exposure to ECE material
– Early experience of lab work and problems
– Students appreciate:
• conceptual focus
• immediate feedback in experiments
– Kolb Learning Styles: Convergers and
Assimilators benefited likewise
– Appeal to self-motivation effective
Some Scenes